Rec Room (OOCs)
As it turns out, it is a joke that's been going around for around 80 years.
Which kind of indicates that the attitude is more Old School than modern, but since the US wasn't part of the original joke, it's only been adapted to us.
Of course, you have to remember how much the US public was being influenced by the major newspapers at the time, who dumped their personal beliefs and agendas on everyone.
We got 'dragged' into WWI, which was a 'foreign' war, and we were damned if we were going to get involved in another one, which is why it took Pearl Harbor to get us into WWII. We would have anyway, because Germany and Japan both wanted to conquer the world.
The problem is that besides the American Civil War, we are one country. In half the space over in Europe there are 50 countries that have been at war with one another for over 500 years.
That's where the difference in attitude comes from.